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dsa(1ssl)
NAME
  dsa - DSA key processing

SYNOPSIS
  openssl dsa [-inform PEM | DER] [-outform PEM | DER] [-in filename]
  [-passin arg] [-out filename] [-passout arg] [-des] [-des3] [-idea] [-text]
  [-noout] [-modulus] [-pubin] [-pubout]

OPTIONS
  -inform DER|PEM
	  Specifies the input format. The DER option with a private key uses
	  an ASN1 DER encoded form of an ASN.1 SEQUENCE consisting of the
	  values of version (currently zero), p, q, g, the public and private
	  key components respectively as ASN.1 INTEGERs. When used with a
	  public key it uses a SubjectPublicKeyInfo structure. It is an error
	  if the key is not DSA.

	  The PEM form is the default format. It consists of the DER format
	  base64 encoded with additional header and footer lines. In the case
	  of a private key PKCS#8 format is also accepted.

  -outform DER|PEM
	  Specifies the output format. The options have the same meaning as
	  the -inform option.

  -in filename
	  Specifies the input filename to read a key from or standard input
	  if this option is not specified. If the key is encrypted, there
	  will be a prompt for a pass phrase.

  -passin arg
	  Input file password source. For more information about the format
	  of arg, see the Pass Phrase Arguments section in openssl(1ssl).

  -outfilename
	  Specifies the output filename to write a key to or standard output
	  by is not specified. If any encryption options are set there will
	  be a prompt for a pass phrase. The output filename should not be
	  the same as the input filename.

  -passout arg
	  Output file password source. For more information about the format
	  of arg, see the Pass Phrase Arguments section in openssl(1ssl).

  -des|-des3|-idea
	  These options encrypt the private key with the DES, triple DES, or
	  the  IDEA ciphers respectively before outputting it. There is a
	  prompt for a pass phrase. If none of these options is specified the
	  key is written in plain text. This means that using the dsa utility
	  to read in an encrypted key with no encryption option can be used
	  to remove the pass phrase from a key, or by setting the encryption
	  options it can be use to add or change the pass phrase. These
	  options can only be used with PEM format output files.

  -text	  Prints the public, private key components and parameters.

  -noout  Prevents output of the encoded version of the key.

  -modulus
	  Prints the value of the public key component of the key.

  -pubin  By default, a private key is read from the input file. With this
	  option a public key is read instead.

  -pubout By default a private key is output. With this option a public key
	  will be output instead. This option is automatically set if the
	  input is a public key.

DESCRIPTION
  The dsa command processes DSA keys. They can be converted between various
  forms and their components printed out.  This command uses the traditional
  SSLeay compatible format for private key encryption. Newer applications
  should use the more secure PKCS#8 format using the pkcs8 command.

NOTES
  The PEM private key format uses the header and footer lines:

	-----BEGIN DSA PRIVATE KEY-----
	-----END DSA PRIVATE KEY-----

  The PEM public key format uses the header and footer lines:

	-----BEGIN PUBLIC KEY-----
	-----END PUBLIC KEY-----

EXAMPLES
  To remove the pass phrase on a DSA private key:

	openssl dsa -in key.pem -out keyout.pem

  To encrypt a private key using triple DES:

	openssl dsa -in key.pem -des3 -out keyout.pem

  To convert a private key from PEM to DER format:

	openssl dsa -in key.pem -outform DER -out keyout.der

  To print out the components of a private key to standard output:

	openssl dsa -in key.pem -text -noout

  To just output the public part of a private key:

	openssl dsa -in key.pem -pubout -out pubkey.pem

SEE ALSO
  Commands: dsaparam(1ssl), gendsa(1ssl), rsa(1ssl), genrsa(1ssl)

Index for Section 1ssl

Alphabetical listing for D

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